His bedroom in the family's home in the village of El Fortin, Mexico, remains exactly as he left it -- a simple green plaid blanket draped over the bed.

Jovani Cordova says his brother was kind and worked hard to help their family.

"He was responsible for my mother. In fact, he worked in the sea because of her," he said. "He wanted to improve himself. He didn't want to be poor like us."

The road in the rural community is so bad it's easier to travel by boat. A short ride took Cordova to where he worked, the nearby town of Costa Azul.

Members of the cooperative, where fishermen make an average of $150 a week, still remember the frantic search to find him and Alvarenga after their boat went missing.

"My colleagues went to fish, and the next day they told me by radio that the engine failed and the GPS device was wet. We went to search for them for seven or eight days with the authorities," said Bellarmino Rodrigues, who owned the boat. "The governor gave us a small aircraft, but it was impossible to find them."

Back at the family home, Rios told CNN she was focused on one thing.

"As a mother, I demand that the authorities allow me to talk to the survivor," she said last week. "Only in that way will I know what happened and what he did with the body of my son. I deserve the truth."